Britbox offers a large number of British programming from BBC and ITV. They also sneak in shows from All4. A nice mix of movies, mystery, right down to comedy and game shows. It should be a good streaming service but it has constant technical issues that they can't seem to fix. The biggie (just like AcornTV) is when you use a browser to view their content. After watching a stream for a while you'll be told the content is not available on this device. Your Watch List will disappear and you then can't watch anything. One screwup after another. They do fix it eventually but the wait is annoying.
It just seems that there isn't a streaming service anywhere out there that hires IT people that actually know what they're doing. They just keep bandaiding everything. Oh ya and keep raising the price with no improvements.